Heat oven to 350°F. In small bowl, combine brown sugar and margarine; blend well. Spread in bottom of ungreased 9-inch round cake pan. Arrange pineapple slices and maraschino cherries over brown sugar mixture. Set aside.
In small bowl, beat egg yolks until thick and lemon colored. Gradually add sugar; beat well. Lightly spoon flour into measuring cup; level off. Add flour, baking powder, salt and pineapple juice; mix well.
In another small bowl, beat egg whites until stiff peaks form. Fold into batter. Pour batter evenly over pineapple slices and cherries.
Bake at 350°F. for 30 to 35 minutes or until toothpick inserted in center comes out clean. Cool upright in pan 2 minutes. Invert cake onto serving plate. Serve warm with whipped cream.